A metering device of this type is known from WO 00/64517. There, the electronic counting module is mounted on the outside on a housing of the metering device.
The object of the invention is to provide a metering device of the type mentioned in the introduction, which has an improved arrangement of the counting module.
This object is achieved in that the electronic counting module has a module housing, the external dimensions of which are adapted to internal dimensions of a reception space, open on at least one side, of the applicator housing, in such a way that the module housing can be inserted completely into the reception space and be fastened in the latter. This affords a complete integration of the electronic counting module into the metering device. The insertion and fastening of the module housing for the electronic counting module in the applicator housing makes it possible, on the one hand, to have a particularly protected accommodation of the counting module and, on the other hand, to have a visually pleasing integration of the counting module into the applicator housing. The reason for this is that, although the counting module has its own module housing, this module housing cannot be seen from outside, since it is integrated in the applicator housing. The modular nature of the counting module results not only in the protection function, but also in simple handling during assembly. The at least one stroke detection means is assigned to a relatively movable pump portion. This means that the stroke detection means and the pump portion are assigned to different components which are arranged movably in relation to one another, irrespective of whether the stroke detection means or the pump portion is moved. One of the two functional parts must in any event be virtually stationary in relation to the other, in order to make stroke detection possible.
The reception space and the counting module are preferably coordinated with one another in such a way that the counting module, which is inserted completely in the reception space, comes to bear with its outer faces in the reception space in such a way that there is no longer any remaining freedom of movement.
In a refinement of the invention, the fastening provided is toolless and releasable. This makes it possible to insert and remove the module housing in a particularly simple way. It is therefore also possible to insert the module housing, including the counting module, into the applicator housing only at a later stage. This is advantageous particularly when the metering device is made available in only premounted state to the user who has to assemble the various parts of the metering device so as to be ready for operation. Moreover, the refinement allows easy exchange or a simple separate disposal of the counting module or of its components.
In a further refinement of the invention, the module housing and the reception space have latching profilings matching with one another, in such a way that the module housing can be latched in the reception space. In this embodiment, advantageously, both the module housing and the applicator housing are produced from plastic. Latching may be releasable or unreleasable. Alternatively, the module housing and the reception space may be coordinated with one another in terms of their size in such a way that the module housing can be fastened nonpositively in the reception space. In this case, too, an embodiment consisting of plastic is preferred.
In a further refinement of the invention, the module housing has an inspection window, behind which the indicator unit is positioned. In a further refinement, the reception space has, spaced apart from a mounting or demounting orifice, an outwardly open clearance, in which the inspection window of the module housing is arranged when the module housing is in the mounted state. In this case, the clearance is coordinated in its dimensions with the inspection window in such a way that the inspection window of the module housing can be viewed at least essentially unrestrictedly from outside. In a preferred refinement, the inspection window is shouldered outward in the manner of a step, in such a way that its marginal edges form, together with corresponding margins of the clearance of the applicator housing, latching profilings which match with one another and which latch the module housing in the reception space. In a special development of the invention, the inspection window is a one-piece part of the module housing. This makes it possible for the module housing to have a particularly simple and cost-effective design.
It is particularly advantageous if the reception space into which the module housing is inserted has separately from one another a mounting and demounting orifice, on the one hand, and a clearance for the inspection window, on the other hand. The clearance may in such a case be designed to be smaller than the external dimensions of the module housing, so that a margin of the clearance or the wall itself surrounding the clearance cooperates as a holding portion in securing the module housing.
In a further refinement of the invention, the at least one stroke detection means is designed for digital or analog displacement detection. Digital displacement detection detects one or more instantaneous stroke points during the metering stroke. If the stroke points are detected at the start and end of a stroke operation, it can be ascertained whether a complete or only a partial stroke has taken place. Analog displacement detection detects a displacement distance which ensures additional evaluation possibilities, such as stroke speed, metering volume and the like.
In a further refinement of the invention, the data processing processor is arranged on a circuit board which is arranged in the module housing in such a way that it can execute deflecting movements in at least one direction. It is thereby possible to compensate tolerances in the production and mounting of the metering device. Moreover, the situation is prevented where the circuit board or the data processing processor may be damaged during a stroke operation.
In a further refinement of the invention, the indicator unit comprises a, liquid crystal display. As a result, corresponding information and data can be read off in a clearly visible way on the indicator unit.
In a further refinement of the invention, the module housing is of liquidtight or gastight design. The possibilities for using the metering device are thereby further improved. As a result, an insulation of the components within the module housing with respect to surrounding influences is achieved.
In a further refinement of the invention, the current source is designed as a battery or accumulator and is inserted in the manner of a sandwich between the liquid crystal display and the circuit board. This allows a particularly space-saving accommodation of the current source within the module housing. Moreover, the battery or accumulator forms a stable support for the external components, to be precise the liquid crystal display and the circuit board.
In a further refinement of the invention, the module housing has a closing cover which, in the mounted state, faces the stroke-movable pump portion. The closing cover allows the mounting of the components within the module housing and, depending on releasability, also renewed demounting.
In a further refinement of the invention, the closing cover is connected positively, nonpositively or materially integrally to a container-like housing portion. The module housing is preferably designed in two parts, in that, on the one hand, the container-like housing portion is provided and, on the other hand, the closing cover is provided, which is preferably latched, clamped, adhesively bonded or welded on the container-like housing portion.
In a further refinement of the invention, the closing cover comprises at least one touch-contact boss which is assigned to the stroke detection means and which is mounted movably between a switching position and a position of rest. The closing cover thereby assumes a multiple function, since, in addition to the closing function for the module housing, it also includes the actuation of the stroke detection means.
In a further refinement of the invention, the closing cover comprises a diaphragm face which is designed as a solid-state joint for the movability of the touch-contact boss. This refinement makes it possible for the closing cover to have a watertight configuration, since the closing cover can be designed to be continuously closed over its entire extent by virtue of the preferably elastically, movable diaphragm face.
In a further refinement of the invention, the diaphragm face is integrated in one piece into a dimensionally stable frame portion of the closing cover. The dimensionally stable frame portion assumes the carrying and closing function with regard to the module housing. The diaphragm face provides the movability of the touch-contact boss and at the same time ensures the leaktightness of the closing cover.